There's an extension for that. Quite handy for in-browser terminals like one in AWS etc.

https://addons.mozilla.org/en-US/firefox/addon/ctrl-shift-c-...

I installed this extension 5 minutes ago and it's already such an improvement. Never occured to me that there can be extensions to override shortcut defaults.

Thanks!

as a matter of fact... yes https://i.imgur.com/0uxzr4H.png

This was my first thought too!